to add to this excellent critique, you're tense. Loosen up man! tension = speed destruction. I could almost feel the tension in your arms, and that was through a crappy low-res video on youtube!

You have absolutely NO power in your punches, not just because of what Taison said, but because you're pulling them. I could stand there all day with you punching me like that and you wouldn't do any damage even though you're far more muscular than I am. Why? Because you're not connecting with any power. You're pulling your punches back before they even hit. It's like you're fighting a tree, and you're afraid of barking (haha) your knuckles on it. Don't punch TO the target, punch THROUGH the target.